A differential circuit operates on the difference between two input signals. Its structure couples together two half-circuits and its performance largely depends on the symmetry between these two half-circuits.
The linearity performance of differential circuits is critical in certain applications, such as in communication receivers. Oftentimes, communication receivers must process very strong unwanted or interfering signals without corrupting the wanted or desired communication signal. In many applications, the desired communication signal can be extremely small. It would therefore be advantageous to have differential circuits with improved linearity and low distortion.